Long-term debt (Detail) - CAD ($) $ in Millions |
Jun. 30, 2025 |
Dec. 31, 2024 |
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| Debt Disclosure [Abstract] | |||||||||||||||||||||||||||||||||||||||||||||||||
| Long-term debt | $ 3,447 | $ 3,447 | |||||||||||||||||||||||||||||||||||||||||||||||
| Finance leases | 536 | 545 | |||||||||||||||||||||||||||||||||||||||||||||||
| Total long-term debt | [1] | $ 3,983 | $ 3,992 | ||||||||||||||||||||||||||||||||||||||||||||||
| Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration] | Total long-term debt | Total long-term debt | |||||||||||||||||||||||||||||||||||||||||||||||
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- References No definition available.
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- Definition Present value of lessee's discounted obligation for lease payments from finance lease, classified as noncurrent. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Indicates line item in statement of financial position that includes noncurrent finance lease liability. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of long-term debt and lease obligation, classified as noncurrent. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt classified as noncurrent. Excludes lease obligation. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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